The present invention was developed in conjunction with an effort to provide a Cartesian grid to interconnect adjacent transceivers in a laboratory test environment as directed from a programmable computer control console. In view of the frequencies involved and the isolation required between ports, there was no known way of accomplishing such an interconnection even with manual switching. The added requirement of dynamic computer controlled switching of signals between ports and the requirement that the signal transmission be bidirectional merely added to the complication. One embodiment of the present inventive concept comprises an eight port device using high isolation, low insertion loss resistive dividers, absorptive switches, and attenuators. The interconnection between four of the ports is uncontrolled, while there is interconnect control circuitry associated with the remaining four ports. The design of the RF switch matrix is such that switched interconnect paths between any two of the eight ports are possible provided that at least one of the two ports has the interconnect control circuitry. Any port may be connected to any other port with return loss virtually independent of the path selected. Each switch path may be actuated independently or simultaneously.
It is thus an object of the present invention to provide a multipurpose device, which can accomplish a plurality of signal switching and attenuation functions, all operating with high frequencies, and maintaining a large amount of signal isolation between ports as appropriate.